1. Field of the Invention
The present invention generally relates to a testing technology field, and more particularly to a testing system capable of reducing testing cost.
2. Description of Prior Art
A liquid crystal display device mainly comprises a liquid crystal panel and a backlight module. The liquid crystal panel comprises a thin film transistor (TFT) substrate, a color filter (CF) substrate, and a liquid crystal layer disposed between the TFT substrate and the CF substrate.
In polymer stabilization vertical aligned processes, array processes, cell processes, or other processes, the TFT substrate is required to be tested for checking whether functions of elements (such as thin film transistors) on the TFT substrate are normal.
Please refer to FIG. 1, which shows a testing system in the prior arts. The testing system comprises a probe frame 10, a plurality of probes 12, and a TFT substrate 14. The probes 12 are disposed at the probe frame 10 and made of elastic metallic material. Before testing, a plurality of pad P1˜P5 is required to be manufactured on the TFT substrate 14 and elements (not shown) which are required to receive input signals are respectively and electrically connected with the pads P1˜P5. When testing, the probes 12 of the probe frame 10 are correspondingly aligned to and contact with the pads P1˜P5 for checking whether functions of the elements on the TFT substrate 14 are normal.
However, there might exist misalignments between the probes 12 of the probe frame 10 and the corresponding pads P1˜P5, or lengths of the probes 12 are different since the probes 12 fail to be restored elastically after long term usage, so that the probes 12 have poor contact with the corresponding pads P1˜P5 and wrong testing results are produced.
To improve the above-mentioned problem of poor contact, another testing system in the prior arts is shown in FIG. 2. A difference between the testing systems in FIG. 1 and FIG. 2 is that the testing system in FIG. 2 comprises the pads P1˜P5 and pads P1′˜P5′. The pads P1˜P5 are respectively and electrically connected with the pads P1′˜P5′. That is, a quantity of the pads in FIG. 2 is twice a quantity of the pads in FIG. 1. Take the pads P1 and P1′ for example, when testing, one of the pads P1 and P1′ can be randomly selected for being applied by a testing signal. The problem of whether the poor contact occurs can be determined by detecting the other one of the pads P1 and P1′. When the problem of the poor contact occurs, the alignments between the probes 12 of the probe frame 10 and the corresponding pads P1˜P5 and P1′˜P5 are adjusted or the position of the TFT substrate 14 is adjusted.
However, since the quantity of the pads in the testing system in FIG. 2 is twice the quantity of the pads in the testing system in FIG. 1, the cost of the testing system and the complexity of disposed circuits on the TFT substrate 14 are increased.
Therefore, there is a need to solve the above-mentioned problems of the testing system in the prior arts.